What is the domain of f(x) = cos(x)?

A)the set of real numbers Negative 2 pi less-than-or-equal-to x less-than-or-equal-to 2 pi
B)the set of real numbers Negative 1 less-than-or-equal-to x less-than-or-equal-to 1
C)the set of real numbers 0 less-than-or-equal-to x less-than-or-equal-to 2 pi
D)the set of all real numbers

ha!

i just did this!

18. g

20. h 30 degree turn.

21. d 90 degree angles

and also 19 is a. a sphere not a cirlcle

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step-by-step explanation:

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